Discharging fluid from a container



Feb. 28, 1967 K. G. PAGE DISCHARGING FLUID FROM A CONTAINER 3 SheecS-Sheetl Filed Dec. 27, 1965 FEGG.

INVENTOP I- KENNETH GEORGE PAGE A'ITORNEY Feb. 28, 1967 PAGE DISCHARGING FLUID FROM A CONTAINER 5 Sheets-Sheet 2 Filed Dec. 27, 1965 FIG. 7'.

INVENTOR I- KENNETH GEORGE PAGE ATTORNEY Feb. 28, 1967 K. G. my: 3,306503 DISCHARGING FLUID FROM A CONTAINER Filed Dec. 27, 1965 3 Sheets-Sheet 5 lNVENTOR'.-

KENNETH GEORGE PAGE ATTORNEY United States Patent The invention relates to the discharge of fluid (hereinafter referred to as the first fluid) from a container by introducing other fluid (hereinafter referred to as the second fluid) into a collapsible bag positioned inside the container, thereby to expand the bag, the bag on expanding occupying an increasing volume of the container and thereby displacing and expelling the first fluid through at least one outlet leading from the container.

A difficulty that has arisen in connection with this method of discharging the first fluid from the container is that Where the bag is arranged inside the container prior to filling the latter with the first fluid, the outer surface of the bag will be in contact with the first fluid not only during expansion of the bag to discharge the first fluid from the container but also during the whole of the time the first fluid is stored in the container. That arrangement is unsatisfactory where the first fluid is incompatible with the material of the bag, because the first fluid could cause the bag to become porous or otherwise damaged. Alternatively the bag material could adversely affect the stability of, or contaminate, the first fluid. Damage to the bag by the first fluid during the period of storage could result in leakage into the container of the second fluid when the latter has been introduced into the bag to expand it, thereby affecting the extent of the expansion of the bag and hence the efficiency of discharge of the first fluid from the container and also resulting in contamination of the first fluid by the second fluid.

An object of the invention is to provide a container including a collapsible bag which is capable of being expanded to expel the first fluid from the container but in which the collapsed :bag is not permitted to come into contact with the first fluid until the operation of expanding the bag to expel said first fluid from the container has commenced.

According to the invention, a container for a first fluid includes a compartment of which the interior is isolated by a closure member from the interior of the remainder of the container, until the first fluid is to be discharged from the container, the compartment initially containing a collapsed bag arranged to be expanded by introducing a second fluid into the bag, the closure member being arranged to be opened by the action of introducing the second fluid to the bag and to permit at least a portion of the collapsed bag to enter the container and there to be expanded to displace the first fluid through an outlet ,of the container.

In a container in accordance with the invention, the bag when collapsed closely surrounds a flexible tube extending from one end of the bag and through which the second fluid is introduced into the bag, said one end of the bag and the inlet end of the flexible tube being anchored in the compartment and the tube and the collapsed bag initially being rolled up into a spiral and housed in the compartment, whereby the introduction of the second fluid to the compartment and into the flexible tube will open the closure member of the compartment and cause the flexible tube and the collapsed bag to be unrolled from the compartment into the remainder of the container and to continue to unroll until the flexible tube is substantially straight, the second fluid then ice entering the bag through the outlet end of the tube thereby causing the bag to expand away from the flexible tube. A restrictor may be provided in the outlet end of the flexible tube. By providing the restrictor, the tube will be held substantially straight, after it has been unrolled, by the flow of said second fluid into the bag.

In a container in accordance with the immediately preceding paragraph, the closure member may be a removable bung or cap, arranged to be pushed outwardly of the compartment into the remainder of the container as a result of the introduction of the second fluid to the bag, thereby to open the compartment to the interior of the remainder of the container and so to permit at least a portion of the bag to enter the container as the bag is unfolded or unrolled. To ensure that the first fluid cannot enter the compartment and come into contact with the bag before the operation of discharging said first fluid has commenced, the bung or cap may be sealed around its periphery by a pressure rupturable seal capable of breaking as a result of the introduction of the second fluid. As a considerable force may be necessary to rupture the seal, the pressure of the second fluid would have to be allowed to increase until the seal has ruptured. It is desirable that this increased pressure should not act initially on the bag, thereby to avoid damaging the bag. Therefore according to a further feature of the invention, the compartment may also contain a piston to which the second fluid is to be applied and initially closed valve means to prevent the second fluid from entering the bag, the piston being arranged to be pushed by the pressure of the second fluid to rupture the seal an on continued movement to push the bung or cap into the interior of the remainder of the container and also to open said valve means thereby to admit the second fluid to the bag.

The first fluid may be any liquid or gas but the container in accordance with this invention is especially intended to be used for hydrogen peroxide which is to be supplied to a combustion chamber of a rocket engine. The second fluid may be any liquid or gas, e.g., water or compressed air.

By way of example three containers in accordance with the invention will now be described with reference to the accompanying drawings, in which:

FIGURE 1 is an axial section through the first container including a compartment containing a bag by which the first fluid in the container can be displaced and discharged therefrom by expansion of the bag by the introduction thereto of the second fluid, the bag being shown in the position in the compartment which it occupies prior to commencement of the discharging operation;

FIGURE 2 is a section on the line 11-41 in FIG- URE 1;

FIGURES 3, 5 and 6 are respectively axial sections similar to FIGURE 1 but showing subsequent positions of the bag during the discharge of fluid from the container;

FIGURE 4 is a section on the line IVIV in FIG- URE 3;

FIGURE 7 is a section through the second container including a compartment containing a bag by which the fluid in the container is to be discharged, the bag being shown in the position in the compartment which it occupies prior to commencement of the discharging operation, and

FIGURE 8 is an axial section of the compartment and adjacent part of the third container.

Referring to FIGURES 1 to 6, the container 1 for the first fluid, e.g. hydrogen peroxide, has at its left-hand end, as viewed in FIGURES 1, 3, 5 and 6, a compartment 2,

in the form of a piston slidable in a rectangular casing 8 communicating with a pipe 3 through which the second fluid, e.g. water, is passed when discharge of the first fluid is to take place. The compartment 2 contains a bag of collapsible material of low permeability which, as will be seen from FIGURE 1, is initially, i.e. before discharge of the first fluid commences, in a collapsed state and rolled up into a spiral and enclosed in the compartment 2 by a bung 4 or cap, fitted into the casing 8. Thus the first fluid in the container 1 does not come into contact with the bag 5 during the whole time that it is stored in the container 1.

As will be seen most clearly from FIGURE 6, the bag 5 is attached around its mouth at its left-hand end to the end wall 7 of the compartment 2 which is opposite the bung 4. The bag 5 is completely closed except that a flexible pipe 6, positioned within and extending substantially the full length of the bag, extends from the end of the bag adjacent the wall 7 and passes therethrough, where it communicates with the pipe 3.

Before the container 1 is filled, the bag 5 is collapsed and is pleated to form a flattened sleeve closely surrounding the pipe 6 which is also flattened (see FIGURE 4). The pleated bag 5 and the flattened pipe 6 are then rolled up into the aforesaid spiral and placed in the compartment 2, which is then closed by the bung 4 (see FIG- URES 1 and 2). The container 1 can then be filled with the first fluid through an orifice 9 and can safely be stored without fear of it having any damaging effect on the bag 5.

When the first fluid is to be discharged from the container 1 through the orifice 9, the second fluid, e.g. water, is introduced through the pipe 3 in the direction of the arrow X shown at the left-hand end of FIGURES 3, 5 and 6. The water after entering the casing 8 will apply pressure to the rear wall 7 of the compartment 2, thereby causing it to slide a predetermined distance within the casing 8 and to push the bung 4 therefrom into the interior of the container 1, as shown in FIGURES 3 to 6, thereby opening the interior of the compartment 2 to the interior of the remainder of the container 1, so as to permit the bag 5 and the tube 6 to be unrolled, as now explained. Water will also enter the mouth of the pipe 6, thereby causing the pipe to expand and to straighten progressively, as indicated in FIGURE 3, until it reaches the position shown in FIGURE 5. When this stage has been reached, water will flow along the whole length of the pipe 6 until it reaches the far end thereof, where it will flow into the bag 5 as shown in FIGURE 5. The bag 5 will then begin to expand radially outwardly, as indicated in FIG- URE 5, and continued introduction of water through the pipe 6 will cause the bag 5 to expand, as shown in FIG- URE 6, until it substantially fills the interior of the container 1. As the bag 5 expands, it will displace the first fluid from the container 1 through the orifice 9. A restrictor 6a (see FIGURES 5 and 6) is provided at the outlet end, i.e. the right-hand end of the tube 6. By providing the restrictor, the tube is more likely to remain straight after it has been unrolled and while the second fluid is passed through it to enter and expand the bag. To prevent the orifice 9 from being closed by the bag 5 as the latter expands, a perforated and dimpled liner 10 is provided within the container 1. As the first fluid is displaced by the bag 5 as the latter expands, the first fluid will flow through holes in the liner 10 and will pass between the liner and the wall of the container 1 to the orifice 9.

Referring to FIGURE 7, the second container 11 has a compartment 12 formed at its left-hand end and closed to the interior of the remainder of the container 11 by .a piston 13, mounted for sliding movement on a guide rod 14 extending through the container 11. The compartment 12 initially contains a collapsed bag 15 of substantially impermeable material, which is folded in the manner of a cylindrical bellows or concertina anchored at one end to the compartment 12 and at the other end to the piston 13. When the container 11 has been filled with the first fluid through an orifice, not shown, this fluid is prevented from coming into contact with the folded bag 15 by the piston 13. When the first fluid is to be discharged from the container 11, a second fluid, e.g. water, is applied to the back of the piston 13 in the direction of arrows Y there'by forcing the piston 13 from the compartment 12 and gradually extending the bag axially along the guide rod 14. The piston 13 will travel along the guide rod 14 until it engages the other end of the container 11, which may be in the form of a pocket 16 into which the piston 13 enters as indicated by broken lines 13. When the piston 13 reaches the position 13', the second fluid will cause the 'bag 15 to expand until it substantially fills the container 11. An intermediate state of the bag is shown by broken lines at 15' at the right-hand end of FIGURE 7.

In any of the containers described hereinbefore, the bung 4 or piston 13 may be sealed around its periphery to the adjacent wall of the compartment 2 or 12 by a pressure-rupturab-le seal, for example an aluminium alloy seal, considerable pressure by the second fluid on the bung or piston being necessary to rupture the seal. It is desirable that this extreme pressure should not suddenly be applied to the bag, as the latter could be torn from its anchorage in the compartment. FIGURE 8 shows how the tearing of the bag can be avoided in a compartment similar to that shown in FIGURE 7, the same reference numerals being used for like parts appearing in the two figures.

Referring to FIGURE 8, the container 11 has a compartment 12 formed therein, the end of the compartment adjacent the interior of the container 11 being closed initially by a piston 13 with the bag 15 attached at one end to the piston 13, as in FIGURE 7. This attachment is made by a clamping ring 28 held against the inside surface of the head of the piston 13 by screws 29. The piston 13 is slidable on the guide rod 14 and is held in its initial position, as illustrated, by an aluminium alloy seal 20 between the rod 14 and the bore of the piston 13 and by a further similar seal 21 between the periphery of the piston 13 and the compartment 11. Unlike the arrangement shown in FIGURE 7, the other end of the bag 15 is attached to the head of another piston 17 also slidable on the guide rod 14 behind (i.e. at the left-hand end) the piston 13. The attachment of the bag 15 to the piston 17 is made by a clamping ring 18, secured to the head of the piston 17 by means of bolts 19. The piston 17 has a central tubular hub 22, which like the piston 17 itself is open to the second fluid, e.g. water, supplied to the interior of the compartment 12 through an inlet 23. Water initially entering the hub 22 passes into the adjacent end of the guide rod 14, which has an axial passage 26 communicating with radial passages 24 therein. The passages 24 are initially closed by valve means constituted by a tubular hub 25 of the piston 13 but subsequently communicate with the interior of the bag 15, when the hub 25 opens the passages 24, as later described. The container 11 has a perforated and dimpled liner 30 similar to the liner 10 in the container of FIGURES 1-6 and provided for the same purpose.

In operation, the second fluid acts first on the piston 17 and pushes it into contact with the piston 13. The resulting axial force on the piston 13 breaks the seals 20 and 21 and so the piston 13 will travel along the guide rod 14, taking with it the adjacent end of the bag 15. After the piston 13 has travelled a short distance, the passages 24 will be uncovered by the hub 25 and the second fluid will enter the interior of the bag 17. By this arrangement the extreme pressure required to break the seals 20 and 21 will not be applied initially to the bag 15 which will not therefore be so liable to 'be torn from its anchorage. Thereafter the piston 13 and bag 15 will operate as for the container of FIGURE 7.

An arrangement similar to that shown in FIGURE 8 and having a second piston, such as 17, engageable with the piston forming the compartment 2 may be applied to the container shown in FIGURES 1 to 6.

What I claim as my invention and desire to secure by Letters Patent of the United States is:

1. A container for a first fluid, a compartment communicatible with the interior of said container, a closure member for said compartment whereby the interior of the compartment is isolated from the interior of the rernainder of the container, until the first fluid is to be discharged from the container, a collapsed bag initially housed completely within the compartment, a flexible tube positioned within said bag and extending from one end thereof, means for introducing a second fluid into said bag through said flexible tube, said one end of said bag and the inlet end of said flexible tube being anchored in said compartment and said flexible tube and said collapsed bag initially being rolled up into a spiral and housed in said compartment, whereby the introduction of said second fluid to said compartment and into said flexible tube will open said closure member of said compartment and cause said flexible tube and said collapsed bag to be unrolled from said compartment into the remainder of said container and to continue to unroll until said flexible tube is substantially straight, said second fluid then entering said balg through the outlet end of said tube, thereby causing said bag to expand away from said flexible tube.

2. A container as claimed in claim 1 in which a restrictor is provided in the outlet end of said flexible tube.

3. A container for a first fluid, a compartment communicatible with the interior of said container, a closure member for said compartment whereby the interior of the compartment is isolated from the interior of the re mainder of the container until the first fluid is to be discharged from the container, a collapsed bag initially housed completely within the compartment and means for introducing a second fluid into the bag, thereby to open the closure member and cause at least a portion of the bag to leave the compartment and to enter said container and there be expanded to displace said first fluid through an outlet of said container, said closure member being a removable bung sealed around its periphery by a pressure-rupturable seal and said compartment also including a piston to which said second fluid is to be applied and initially-closed valve means to prevent said,

second fluid from entering said bag, said piston being arranged to be pushed by the pressure of said second fluid to rupture said seal and on continued movement to push said bung into the interior of the remainder of said container and also to open said valve means thereby to admit said second fluid to said bag.

References Cited by the Examiner UNITED STATES PATENTS 280,830 7/1883 Jameson 22-2-3865 2,671,577 3/1954 Remington et al. 22254l X 3,072,296 1/1963 Isreeli 222-386.5 X 3,083,875 4/1963 Welty et al. 222

ROBERT B. REEVES, Primary Examiner.

N. L. STACK, Assistant Examiner. 

1. A CONTAINER FOR A FIRST FLUID, A COMPARTMENT COMMUNICATIBLE WITH THE INTERIOR OF SAID CONTAINER, A CLOSURE MEMBER FOR SAID COMPARTMENT WHEREBY THE INTERIOR OF THE COMPARTMENT IS ISOLATED FROM THE INTERIOR OF THE REMAINDER OF THE CONTAINER, UNTIL THE FIRST FLUID IS TO BE DISCHARGED FROM THE CONTAINER, A COLLAPSED BAG INITIALLY HOUSED COMPLETELY WITHIN THE COMPARTMENT, A FLEXIBLE TUBE POSITIONED WITHIN SAID BAG AND EXTENDING FROM ONE END THEREOF, MEANS FOR INTRODUCING A SECOND FLUID INTO SAID BAG THROUGH SAID FLEXIBLE TUBE, SAID ONE END OF SAID BAG AND THE INLET END OF SAID FLEXIBLE TUBE BEING ANCHORED IN SAID COMPARTMENT AND SAID FLEXIBLE TUBE AND SAID COLLAPSED BAG INITIALLY BEING ROLLED UP INTO A SPIRAL AND HOUSED IN SAID COMPARTMENT, WHEREBY THE INTRODUCTION OF SAID SECOND FLUID TO SAID COMPARTMENT AND INTO SAID FLEXIBLE TUBE WILL OPEN SAID CLOSURE MEMBER OF SAID COMPARTMENT AND CAUSE SAID FLEXIBLE TUBE AND SAID COLLAPSED BAG TO BE UNROLLED FROM SAID COMPARTMENT INTO THE REMAINDER OF SAID CONTAINER AND TO CONTINUE TO UNROLL UNTIL SAID FLEXIBLE TUBE IS SUBSTANTIALLY STRAIGHT, SAID SECOND FLUID THEN ENTERING SAID BAG THROUGH THE OUTLET END OF SAID TUBE, THEREBY CAUSING SAID BAG TO EXPAND AWAY FROM SAID FLEXIBLE TUBE. 